Heart transplantation in heart failure: The prognostic importance of body mass index at time of surgery and subsequent weight changes

Background: Heart transplantation is an important treatment for end-stage chronic heart failure. We studied the effect of body mass index (BMI), and the effect of subsequent weight change, on survival following transplantation in 1902 consecutive patients. Methods and results: Patients were recruited from: London (n = 553), Berlin (N = 971) and Boston (N = 378). Patients suitable for transplantation due to symptoms, low left ventricular ejection fraction (≤ 30%) and peak oxygen consumption (≤ 16 ml kg^{- 1} min^{- 1}) (N = 237) were used as a comparator. In surviving transplanted patients, average duration of follow-up was 80 (SD 34) months. There were 805 deaths. One year survival was 72.7% (95% CI 72.68-72.72) and 5 year survival was 60.96% (61.94-61.99). Baseline BMI did not effect survival either as a continuous variable (hazard ratio (95% CI): 1.02; 0.99-1.04). Weight loss between transplant and 3 months was associated with worse survival (HR (95% CI) 2.6 (1.42-4.74)) compared with those who gained weight. In the reference group, increasing body mass index was related to survival. Conclusions: Chronic heart failure patients with very low body weight can be transplanted successfully. The presence of underweight need not be an exclusion criterion for heart transplantation. Underweight patients appear to have a greater benefit from transplantation. Body weight increases after transplantation are not associated with adverse prognosis.